🏥 Stations

🧠 Qbank

📖 Book

😃 More

💳 Pricing

🔒 Dashboard

📖 OSCE Learning

🔒 OSCE Stations

🔒 Qbank

🔐 Membership
Share your insights

Help us by sharing what content you've recieved in your exams


Fatigue

Medicine > Endocrine & metabolic

Differential Diagnosis Schema 🧠

Psychiatric Causes

  • Depression: Persistent low mood, anhedonia, and early morning waking, often accompanied by fatigue.
  • Anxiety: Chronic worry, muscle tension, and sleep disturbances leading to fatigue.
  • Chronic Fatigue Syndrome: Severe, disabling fatigue with no identifiable physical cause, often associated with sleep disturbances and cognitive difficulties.
  • Adjustment Disorder: Fatigue occurring in response to a significant life stressor, often with other symptoms of depression or anxiety.

Endocrine and Metabolic Causes

  • Hypothyroidism: Fatigue, weight gain, cold intolerance, and constipation, often with bradycardia and dry skin.
  • Diabetes Mellitus: Fatigue with polyuria, polydipsia, weight loss, and blurred vision, often due to poor glycemic control.
  • Adrenal Insufficiency: Fatigue, hypotension, weight loss, and hyperpigmentation; may be primary (Addison’s disease) or secondary.
  • Chronic Kidney Disease: Fatigue associated with anemia, electrolyte disturbances, and symptoms of uremia.
  • Hypercalcemia: Fatigue, polyuria, polydipsia, constipation, and confusion; often due to hyperparathyroidism or malignancy.
  • Vitamin D Deficiency: Fatigue, muscle weakness, and bone pain; often associated with low calcium and phosphorus levels.

Infective Causes

  • Infectious Mononucleosis: Fatigue, fever, sore throat, and lymphadenopathy, particularly in young adults.
  • HIV Infection: Persistent fatigue with associated symptoms such as weight loss, lymphadenopathy, and recurrent infections.
  • Viral Hepatitis: Fatigue with jaundice, dark urine, and right upper quadrant pain; may have a history of exposure risk.
  • Tuberculosis: Chronic fatigue, weight loss, night sweats, and cough, particularly in high-risk populations.
  • Endocarditis: Fatigue, fever, night sweats, and a new heart murmur, particularly in patients with a history of valve disease or intravenous drug use.
  • Chronic Infections: Fatigue associated with chronic bacterial or parasitic infections, often in endemic areas.

Hematological and Oncological Causes

  • Anemia: Fatigue, pallor, shortness of breath, and dizziness; may be due to iron deficiency, vitamin B12 deficiency, or chronic disease.
  • Malignancy: Fatigue, weight loss, night sweats, and symptoms related to specific cancers (e.g., lymphoma, leukemia, solid tumors).
  • Multiple Myeloma: Fatigue, bone pain, recurrent infections, and renal impairment in older adults.
  • Lymphoma: Persistent fatigue, lymphadenopathy, fever, and night sweats.
  • Leukemia: Fatigue, pallor, bruising, and frequent infections, often with abnormal blood counts.
  • Myelodysplastic Syndromes: Fatigue, anemia, and other cytopenias, often in older adults.

Cardiopulmonary Causes

  • Chronic Heart Failure: Fatigue, dyspnea, orthopnea, and peripheral edema, often with a history of ischemic heart disease or hypertension.
  • Chronic Obstructive Pulmonary Disease (COPD): Fatigue, chronic cough, dyspnea, and history of smoking or exposure to lung irritants.
  • Obstructive Sleep Apnea: Fatigue, daytime sleepiness, snoring, and morning headaches, often with obesity or a large neck circumference.
  • Pulmonary Hypertension: Fatigue, dyspnea on exertion, and signs of right heart failure, often with underlying lung disease or connective tissue disorder.
  • Ischemic Heart Disease: Fatigue, chest pain, and dyspnea on exertion, often with risk factors such as diabetes, hypertension, and smoking.
  • Atrial Fibrillation: Fatigue, palpitations, dyspnea, and irregular pulse, often with underlying cardiac or systemic disease.

Key Points in History 🥼

Onset and Duration

  • Acute vs. Chronic: Acute fatigue may suggest infection, anemia, or acute cardiac causes, while chronic fatigue often points to systemic diseases like hypothyroidism or chronic kidney disease.
  • Intermittent vs. Persistent: Intermittent fatigue may be related to lifestyle factors, while persistent fatigue raises suspicion of underlying chronic conditions.
  • Time of Day: Fatigue that is worse in the morning may suggest depression, while evening fatigue may be more related to physical exertion or sleep disorders.
  • Impact on Daily Activities: Understanding how fatigue affects daily life can help gauge severity and guide management.

Associated Symptoms

  • Weight Loss: May indicate malignancy, chronic infection, or hyperthyroidism.
  • Fever or Night Sweats: Suggests infection, malignancy (e.g., lymphoma), or autoimmune disease.
  • Sleep Disturbances: May be related to depression, anxiety, sleep apnea, or chronic pain.
  • Mood Changes: Depression or anxiety may present with predominant fatigue and should be considered in the differential diagnosis.
  • Dyspnea: Suggests cardiopulmonary causes such as heart failure, COPD, or pulmonary hypertension.
  • Pain: Chronic pain syndromes like fibromyalgia or chronic fatigue syndrome often have associated fatigue.
  • Palpitations: May indicate arrhythmias such as atrial fibrillation, or anxiety.
  • Gastrointestinal Symptoms: Consider chronic liver disease, celiac disease, or inflammatory bowel disease.
  • Infection Risk: Consider HIV, tuberculosis, or other chronic infections in high-risk individuals.
  • Neurological Symptoms: Fatigue with muscle weakness, numbness, or tingling may suggest multiple sclerosis or other neurological disorders.

Background

  • Past Medical History: Relevant conditions include diabetes, thyroid disorders, chronic kidney disease, heart failure, and previous malignancies.
  • Drug History: Consider side effects of medications such as beta-blockers, antidepressants, or antihypertensives, which can contribute to fatigue.
  • Family History: Inquire about family history of chronic illnesses like diabetes, thyroid disorders, or hereditary cancer syndromes.
  • Social History: Assess for lifestyle factors such as stress, alcohol use, recreational drug use, and occupational hazards that may contribute to fatigue.
  • Sleep History: Evaluate sleep patterns, duration, and quality, as sleep disorders like sleep apnea or insomnia are common causes of fatigue.
  • Travel History: Recent travel may suggest infections like malaria, dengue, or other tropical diseases.

Possible Investigations 🌡️

Blood Tests

  • Full Blood Count (FBC): To assess for anemia, infection, or hematological malignancy.
  • Urea and Electrolytes (U&E): To evaluate renal function and electrolyte imbalances, particularly in chronic kidney disease or adrenal insufficiency.
  • Liver Function Tests (LFTs): To assess for liver disease, which can present with fatigue, particularly if associated with jaundice or hepatomegaly.
  • Thyroid Function Tests: To diagnose hypo- or hyperthyroidism, both of which can present with fatigue.
  • C-Reactive Protein (CRP)/Erythrocyte Sedimentation Rate (ESR): To assess for inflammation or infection, particularly in chronic conditions like endocarditis or autoimmune diseases.
  • HbA1c: To evaluate long-term glycemic control in diabetic patients or to screen for diabetes mellitus.
  • Vitamin B12 and Folate Levels: Deficiencies in these vitamins can cause anemia and neurological symptoms contributing to fatigue.
  • Iron Studies: To diagnose iron deficiency anemia, which is a common cause of fatigue, especially in premenopausal women.
  • HIV Serology: Consider in patients with risk factors for HIV infection.
  • Calcium Levels: Hypercalcemia can cause fatigue and is often related to hyperparathyroidism or malignancy.
  • Serum Creatine Kinase (CK): Elevated in conditions such as myositis or rhabdomyolysis, which can present with muscle pain and fatigue.
  • Coeliac Serology: To screen for coeliac disease in patients with gastrointestinal symptoms and fatigue.
  • Autoantibody Screen: To assess for autoimmune conditions such as systemic lupus erythematosus (SLE) or rheumatoid arthritis.

Imaging

  • Chest X-ray: To assess for cardiopulmonary causes of fatigue such as heart failure, lung infection, or malignancy.
  • Echocardiogram: Consider if heart failure, valvular disease, or cardiomyopathy is suspected based on clinical findings.
  • Abdominal Ultrasound: To evaluate for hepatomegaly, splenomegaly, or other abdominal causes of fatigue, particularly in liver disease or malignancy.
  • CT/MRI Scan: May be indicated if there is suspicion of malignancy or other serious conditions based on clinical assessment.
  • Polysomnography: Indicated if obstructive sleep apnea or other sleep disorders are suspected.
  • Brain MRI: Consider if neurological symptoms accompany fatigue, suggesting multiple sclerosis or other central nervous system disorders.

Special Tests

  • 6-Minute Walk Test: To assess exercise tolerance and cardiovascular fitness in patients with fatigue, particularly in chronic heart failure or pulmonary disease.
  • Cognitive Testing: To evaluate for cognitive impairment or depression, which can contribute to fatigue.
  • Thyroid Antibodies: Consider if autoimmune thyroid disease is suspected based on thyroid function tests.
  • Cardiac Stress Test: To evaluate for ischemic heart disease in patients with fatigue and exertional symptoms.
  • Holter Monitoring: For patients with palpitations and fatigue, to detect arrhythmias such as atrial fibrillation.
  • Bone Marrow Biopsy: May be necessary in cases of unexplained anemia, pancytopenia, or suspected hematological malignancy.

No comments yet 😉

Leave a Reply

Endocrine & metabolic